The use of direct deposition electrospinning process in ZnO nanofiber fabrication as double layer (TiO2/ZnO) DSSC: variation of solution flow rate

Electrospinning is a very simple and versatile process by which polymer nanofibers with diameters ranging from a few nanometers to several micrometers can be produced using an electrostatically driven jet of polymer solution (or polymer melt). Significant progress has been made in this process throughout the last decade and the resultant nanostructures have been exploited to a wide range of applications. An important feature of the electrospinning process is that electrospinning nanofibers are produced in atmospheric air and at room temperature. This paper reviews the assembled polyacrylonitrile (PAN)-based carbon nanofibers with various processing parameters such as electrical potential, distance between capillary and collector drum, solution flow rate (dope extrusion rate), and concentration of polymer solution. The average fiber diameter would increase with increasing concentration of the polymer solution and the flow rate. Therefore, the screen distance could also increase but the average electrical potential of the fibers diameter decreases. Electrospinning process can be conducted at higher electrical potentials, lower flow rate, nearer screen distance, and higher concentrations of dope.

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CHARACTERIZATION OF ZnO NANOFIBER ON DOUBLE-LAYER DYE-SENSITIZED SOLAR CELLS USING DIRECT DEPOSITION METHOD

Periódico Tchê Química ◽

10.52571/ptq.v17.n36.2020.278_periodico36_pgs_263_277.pdf ◽

2020 ◽

Vol 17 (36) ◽

pp. 263-277

Author(s):

Zainal ARIFIN ◽

Syamsul HADI ◽

Suyitno SUYITNO ◽

Aditya Rio PRABOWO ◽

Singgih Dwi PRASETYO

Keyword(s):

Solar Cells ◽

Double Layer ◽

Flow Rate ◽

High Efficiency ◽

Dye Sensitized Solar Cells ◽

Electrospinning Process ◽

Deposition Method ◽

Dye Sensitized ◽

Direct Deposition ◽

Sensitized Solar Cells

Solar cells are capable of harvesting energy by converting solar heat into electrical energy through the photovoltaic process. A type of solar cell, namely dye-sensitized solar cells (DSSCs) which based on doublelayer photoanode is attracting researchers and engineers considering its characteristics, e.g., high efficiency, low cost, and available mass-production. The TiO2-ZnO double-layer semiconductor can be obtained from a nanofiber ZnO semiconductor which is deposited with a TiO2 nanoparticle semiconductor. In this study, the direct deposition method was applied using an electrospinning machine. The intention is to directly capture the liquid of electro-jet spun from PVA/Zn(Ac)2 solution onto fluorine-doped tin oxide (FTO) glass. The glass itself is coated with a TiO2 nanoparticle semiconductor. The investigation was addressed to obtain the best tip distance to the collector and the best flow rate in the electrospinning process. The subject environment was designated on the manufacturing process of nanofiber ZnO semiconductors used as double-layer DSSC photoanodes. Variations in flow rates of 3, 4, 5, 6, 7, and 8 μL/minute were applied in the observation. Furthermore, collaboration with the tip to collector distances using a variation of 3, 4, 5, 6, 7, and 8 cm was also considered in this study. Based on these parameters, the effects of the electrospinning process on the morphology of the directly deposited ZnO nanofiber semiconductor were obtained. The results showed that a flow rate of 4 μL/minute and a tip distance to the collector of 8 cm produced a small diameter and uniform morphology. This morphology allowed ZnO nanofibers to have better color absorption and electron excitation. Thus, it was directly proportional to the high efficiency of double-layer DSSCs. The performance value for the 4 μL/min discharge was 2.39%, and the performance value for the 8 cm needle tip distance to the collector was 1.61%.

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The Formation and Morphology of PVA Ferrogel Nanofibre by the Electrospinning Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.650.361 ◽

2010 ◽

Vol 650 ◽

pp. 361-366 ◽

Cited By ~ 1

Author(s):

Tao Yu Wan ◽

Mohammad Chowdhury ◽

George K. Stylios

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Polyvinyl Alcohol ◽

Flow Rate ◽

Electrospinning Process ◽

Magnetic Sensors ◽

Solution Flow Rate ◽

Solution Flow ◽

Fiber Mats ◽

Scanning Electron

Aqueous solutions of polyvinyl alcohol (PVA) with FeCl3 were homogenously mixed and subsequently electrospun; and its characteristics were studied as a function of voltage, tip-target distance and solution flow rate. Fiber mats of (PVA)/FeCl3 composite, in the diameter of 700–1100 nm were prepared by electrospinning. Lower concentrations of solution tended to facilitate the formation of fibres with beads. With increasing concentration, the morphology was improved with smooth and uniform fibres and the increased fibre diameters in the nano range. Spinning voltage also had an important influence on the diameters of the nano fibres, while the collection distance affected fibre diameters. Nano fibres of smaller diameter were formed when lower voltages are applied. The morphology of the electrospun from PVA/FeCl3 nano fibres and their magnetic power was observed and analyzed by scanning electron microscopy (SEM).The fibres produced in this way could potentially be applied to manufacture magnetic sensors, flexible magnets.

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Utilization of Waste of Enzymes Biomass as Biosorbent for the Removal of Dyes from Aqueous Solution in Batch and Fluidized Bed Column

Revista de Chimie ◽

10.37358/rc.20.1.7804 ◽

2020 ◽

Vol 71 (1) ◽

pp. 1-12

Author(s):

Salman H. Abbas ◽

Younis M. Younis ◽

Mohammed K. Hussain ◽

Firas Hashim Kamar ◽

Gheorghe Nechifor ◽

...

Keyword(s):

Experimental Data ◽

Aqueous Solution ◽

Particle Size ◽

Adsorption Capacity ◽

Fluidized Bed ◽

Flow Rate ◽

Fungal Biomass ◽

Solution Flow Rate ◽

Maximum Adsorption Capacity ◽

Solution Flow

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.

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Pellet Softening Process for the Removal of the Groundwater Hardness; Modelling and Experimentation

Al-Qadisiyah Journal for Engineering Sciences ◽

10.30772/qjes.v12i3.603 ◽

2019 ◽

Vol 12 (3) ◽

pp. 135-143 ◽

Cited By ~ 1

Author(s):

Fatin Abdul_kareem Ashoor ◽

Amer D. Zmat ◽

Muthanna H. AlDahhan

Keyword(s):

Calcium Carbonate ◽

Removal Efficiency ◽

Flow Rate ◽

Solution Flow Rate ◽

Pellet Size ◽

Solution Flow ◽

Bed Height ◽

Naoh Solution ◽

Softening Process ◽

Calcium And Magnesium Ions

A lab scale pellet reactor (PR) was designed and fabricated to carry out extensive investigations on the removal efficiency of the hardness of groundwater. The groundwater of 2200 – 2600 mg/L hardness was collected from Abdulla Ibnalhassan wells area located at the west desert of Al-Shinafiyah district (70 km to the southwest of Al-Dewaniyah city, Iraq). Both hydrodynamic parameters of the pellet reactor (porosity and fluidized bed height) and the parameters of calcium carbonate crystallization process (calcium carbonate equilibrium, pellet size, and density) were modeled and compared with the experimental results of the lab scale pellet reactor. The comparison showed that fair agreement between modeled and measured results was observed. The removal efficiency of both calcium and magnesium ions were 62.5-99% and 83-99% respectively. The removal efficiency was found to be strongly dependent on pH and the ratio of NaOH solution flow rate to the groundwater flow rate in the pellet reactor.

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Encapsulation of Menthol in Beeswax by a Supercritical Fluid Technique

International Journal of Chemical Engineering ◽

10.1155/2010/608680 ◽

2010 ◽

Vol 2010 ◽

pp. 1-7 ◽

Cited By ~ 10

Author(s):

Linjing Zhu ◽

Hongqiao Lan ◽

Bingjing He ◽

Wei Hong ◽

Jun Li

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Flow Rate ◽

Saturated Solution ◽

Narrow Particle Size Distribution ◽

Solution Flow Rate ◽

Process Conditions ◽

Solution Flow ◽

Expansion Temperature

Encapsulation of menthol in beeswax was prepared by a modified particles from gas-saturated solutions (PGSS) process with controlling the gas-saturated solution flow rate. Menthol/beeswax particles with size in the range of 2–50 μm were produced. The effects of the process conditions, namely, the pre-expansion pressure, pre-expansion temperature, gas-saturated solution flow rate, and menthol composition, on the particle size, particle size distribution, and menthol encapsulation rate were investigated. Results indicated that in the range of studied conditions, increase of the pressure, decrease of the gas-saturated solution flow rate, and decrease of the menthol mass fraction can decrease the particle size and narrow particle size distribution of the produced menthol/beeswax microparticles. An N2-blowing method was proposed to measure the menthol release from the menthol/beeswax microparticles. Results showed that the microparticles have obvious protection of menthol from its volatilization loss.

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Neutralization Dialysis for Phenylalanine and Mineral Salt Separation. Simple Theory and Experiment

Membranes ◽

10.3390/membranes9120171 ◽

2019 ◽

Vol 9 (12) ◽

pp. 171 ◽

Cited By ~ 1

Author(s):

Anton Kozmai ◽

Elena Goleva ◽

Vera Vasil’eva ◽

Victor Nikonenko ◽

Natalia Pismenskaya

Keyword(s):

Amino Acid ◽

Flow Rate ◽

Solution Concentration ◽

Exchange Capacity ◽

Ion Concentration ◽

Solution Flow Rate ◽

Strong Electrolyte ◽

Mineral Salts ◽

Solution Flow ◽

Hydrodynamic Mode

A simple non-steady state mathematical model is proposed for the process of purification of an amino acid solution from mineral salts by the method of neutralization dialysis (ND), carried out in a circulating hydrodynamic mode. The model takes into account the characteristics of membranes (thickness, exchange capacity and electric conductivity) and solution (concentration and components nature) as well as the solution flow rate in dialyzer compartments. In contrast to the known models, the new model considers a local change in the ion concentration in membranes and the adjacent diffusion layers. In addition, the model takes into consideration the ability of the amino acid to enter the protonation/deprotonation reactions. A comparison of the results of simulations with experimental data allows us to conclude that the model adequately describes the ND of a strong electrolyte (NaCl) and amino acid (phenylalanine) mixture solutions in the case where the diffusion ability of amino acids in membranes is much less, than mineral salts. An example shows the application of the model to predict the fluxes of salt ions through ion exchange membranes as well as pH of the desalination solution at a higher than in experiments flow rate of solutions in ND dialyzer compartments.

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Surface and Morphological Investigation of Synthesized Nanostructured Ridges from Electrospun Polyvinyl Alcohol-Albumin Blend—A Taguchi Design of Experiment Approach

Fibers ◽

10.3390/fib8050029 ◽

2020 ◽

Vol 8 (5) ◽

pp. 29

Author(s):

Jopeth Ramis ◽

Bryan Pajarito ◽

Crisneil Natividad ◽

Mark Jared Van Ocampo ◽

Crizaldy Tugade ◽

...

Keyword(s):

Polyvinyl Alcohol ◽

Flow Rate ◽

Design Of Experiment ◽

Surface Characterization ◽

Taguchi Design ◽

Root Mean Square Roughness ◽

Solution Flow Rate ◽

Radius Of Curvature ◽

Solution Flow ◽

Taguchi Design Of Experiment

We report the synthesis of presumably a “nanoridge” from the electrospinning of a hydrophilic polymer–protein blend. The material exhibits vertical elevation from the substrate, distinct from the morphologies seen in electrospinning. It is hypothesized that the formation of the nanostructured ridges is due to the migration of the charged protein to the apex through a highly polarized electric field in electrospinning conditions. In this study, we assessed the polyvinyl alcohol–egg albumin (PVA–EA) system in a solvent comprising of water, formic and acetic acid, together with the tip-to-collector distance (TCD) and solution flowrate. To quantify the factor effects in the surface properties of the material, a Taguchi design of experiment was used. The ridge heights observed ranged from 84.8–639.9 nm, and the material height is predominantly affected by the PVA–EA ratio and solution flow rate. The root mean square roughness was influenced by the TCD and flow rate, which has values ranging from 11.37–57.56 nm. In evaluating the sharpness of the ridge, we used the radius of curvature, where the TCD highly affects the apex sharpness. The work offers not just a likely new class of morphology, but a new perspective on the surface characterization of an electrospun material which could affect the performance of such a use in biological and physical systems.

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Investigation on the Regeneration Performance of a New Mixed Liquid Desiccant Solution in Falling Film Regenerator

Proceedings ◽

10.3390/proceedings2221374 ◽

2018 ◽

Vol 2 (22) ◽

pp. 1374

Author(s):

Tao Wen ◽

Dan Zhong ◽

Yuanhao Wang ◽

Yimo Luo

Keyword(s):

Flow Rate ◽

Solution Temperature ◽

Solution Flow Rate ◽

Mixed Solution ◽

Falling Film ◽

Liquid Desiccant ◽

Solution Flow ◽

Regeneration Rate ◽

Air Inlet ◽

Selection Of

The present study firstly developed a new kind of mixed liquid desiccant for the purpose of causticity reduction on metal based regenerator. The formula of the mixed liquid desiccant is 25% LiCl + 39% hydroxyethyl urea + 36% water. Experimental results show that the causticity of the mixed solution is much less severe than that of conventional LiCl solution. The regeneration rate increases with the increase of air flow rate and solution temperature and decreases with the increase of air inlet humidity. The air temperature and solution flow rate has negligible influence on the regeneration performance. The present study provides a practical alternative for the selection of liquid desiccant and also give useful guidance for the design of regenerator.

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The Development of Electrospinning Apparatus to Fabricate Nanofiber for Future Material Applications

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.866.244 ◽

2017 ◽

Vol 866 ◽

pp. 244-247

Author(s):

Pattarinee Klumdoung ◽

Piyapong Pankaew

Keyword(s):

Flow Rate ◽

Low Cost ◽

Average Diameter ◽

Operating Conditions ◽

Solution Flow Rate ◽

Syringe Pump ◽

Sem Images ◽

Solution Flow

This research examines the development of a low cost mobile electrospinning system for fabricating nanofiber. The electrospinning system developed in this study consists of a horizontal needle arrangement and a motor which supports the working system that controls the solution flow rate without an external syringe pump. In order to discover the equipment operating conditions for nanofiber fabrication, the distance from the needle to the target was studied. A PVA solution of 8wt% was used and voltage was applied at 13 kV. The needle to target distances were varied from 8-18 cm. At a distance of 10 cm, the SEM images showed that the smallest diameter of the fiber was 119 nm. The average diameter was in the range of 119-240 nm. Concentrations of the 3 different solutions of PVA, PEO and PCL with the variation of voltage at each concentration were studied. The results show the diameter of PVA at 8 wt% and 12%wt are in the range of 127-197 nm and 222-402 nm, respectively. The diameter of PCL solution at a 20 wt% concentration is in the range of 32-60 nm. PEO at 2 wt% and 4wt% was not able to form as a fiber.

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